Answer:
D. 15×4/100×4 = 60/400
Step-by-step explanation:
First I figured out how many photos there are in total, which was by doing 60/.15, since only 15% of the total photos are in black and white. We can already cross out all possibilities that don't have the denominator 400, but we can go a step further by seeing which one is 60/400, or equal to 60/400, which is D. 15×4/100×4 = 60/400.
Let x be the width, length=4x
(4x+x)×2×2=12.5
20x=12.5
x=0.625
Length = 4×0.625=2.5
Area = 2.5×0.625= 1.5625 km square
Answer:
(a) 3.75
(b) 2.00083
(c) 0.4898
Step-by-step explanation:
It is provided that X has a continuous uniform distribution over the interval [1.3, 6.2].
(a)
Compute the mean of X as follows:
(b)
Compute the variance of X as follows:
(c)
Compute the value of P(X < 3.7) as follows:
![P(X < 3.7)=\int\limits^{3.7}_{1.3}{\frac{1}{6.2-1.3}}\, dx\\\\=\frac{1}{4.9}\times [x]^{3.7}_{1.3}\\\\=\frac{3.7-1.3}{4.9}\\\\\approx 0.4898](https://tex.z-dn.net/?f=P%28X%20%3C%203.7%29%3D%5Cint%5Climits%5E%7B3.7%7D_%7B1.3%7D%7B%5Cfrac%7B1%7D%7B6.2-1.3%7D%7D%5C%2C%20dx%5C%5C%5C%5C%3D%5Cfrac%7B1%7D%7B4.9%7D%5Ctimes%20%5Bx%5D%5E%7B3.7%7D_%7B1.3%7D%5C%5C%5C%5C%3D%5Cfrac%7B3.7-1.3%7D%7B4.9%7D%5C%5C%5C%5C%5Capprox%200.4898)
Thus, the value of P(X < 3.7) is 0.4898.
Let's call the angles x and y. We know that supplementary angles must add to 180 degrees, so x+y=180.
Furthermore, we know that x is 75% more than 2y. We can write "75% more than" numerically as 1.75, so x = 1.75(2y).
We can simplify the second equation by multiplying 1.75 and 2 together to get x = 3.5y.
Now we can solve the system of equations by substitution by plugging 3.5y in for x in x+y=180.
(3.5y) + y = 180
Combine like terms.
4.5y = 180
Divide by 4.5
y = 40
Plug y = 40 in and solve for x.
x + 40 = 180
x = 140
The answer is 40 and 140. Hope this helps :)
